1. Field of the Invention
The present invention generally relates to a swivel support for seating such as a boat chair, various vehicle seats and other types of chairs or seats which can swivel and be vertically elevated or lowered and more specifically a swivel support provided with a lock structure which will automatically lock the swivel support in angularly adjusted position about a vertical axis when the support is lowered from its elevated position to its lowered position. Many boats are provided with chairs which can be elevated to provide occupants of the chair with a better position for fishing. Many other swivel chairs and seats can also be elevated or lowered. Boat chairs of this type are conventionally capable of being swiveled or rotated about a vertical axis to enable the occupant to assume different angular positions in relation to the gunwales of the boat for a more effective fishing position. The swivel support of this invention includes a lock structure which will automatically lock the boat chair against rotation or swivel movement when the boat chair is lowered such as when the boat is being driven from one location to another. The lock structure for the chair includes components on the stationary base and the movable component of the chair which interengage in one of a plurality of selected positions about a vertical axis when the boat chair is lowered to lock the boat chair in the selected angular position automatically when the boat chair is lowered.
2. Description of the Prior Art
Boat chairs which can be elevated manually or which are powered by an air lift, gas lift, hydraulic lift or the like are well known and these chairs are also capable of rotating about a vertical axis to enable the occupant to obtain optimum position when fishing. The following U.S. patents relate to developments in this field.
276,830 PA1 1,862,755 PA1 4,278,289 PA1 4,487,452 PA1 4,518,139 PA1 4,655,632 PA1 4,673,155
While the prior patents disclose chairs which are elevatable, capable of swiveling movement and return to a predetermined position when an occupant leaves the chair, the above mentioned patents do not disclose a lock structure in accordance with this invention.